field



(No Model.)

S. D. FIELD.

"PRINTING TELEGRAPH. No. 287,266. Patented Oct. 23, 1883.

rrrc.

STEPHEN D. FIELD, OF NEWV YORK, N. Y., ASSIGNOR TO THE COMMERCIAL v TELEGRAM COMPANY, OF SAME PLACE.

PRINTING-TELEGRAPH.

SPECIFICATION forming part of Letters Patent No. 287,266, dated October 23,1883.

Application filed April 27, 1883. (No model.)

To all whom it may concern.-

Be it known that I, STEPHEN D. FIELD, of New York, in the county of New York and State of New York, have invented a new and useful Improvement in Printing-Telegraphs and I do hereby declaretthat the following is a full and exact description of the same, reference being had to the accompanying drawing, and to the letters of reference marked thereon.

The object of my invention is to provide a 'unison mechanism for printing telegraphs, adapted to be called into action only after several revolutions of the type-wheel. This I ac- I 5 complish by placing the unison-stop upon a wheel receiving motion from the type-Wheel shaft through more or less intermediate gearing, the gearing being so calculated that the wheel carrying the stop shall rotate once only while the type wheel is revolving several times. This is illustrated in the drawing, in which M M A B constitute the ordinary polarized escapement of a printing-telegraph whose type-wheel, or one of whose type-wheels, is designated by the dotted circle 0, mounted on the type-wheel shaft D.

Upon the type-wheel shaft is mounted a pinion, E, meshing into a suitably-supported gearwheel, F, carrying the unison-stop a. As here shown, the pinion has ten teeth and the gearwheel forty; hence the latter would make one revolution to four of the type-wheel. This relation, however, may be varied so as to cause one revolution. of the gear to any desired number of the type-wheel, or a greater number or train or gearing may be interposed between the type-wheel shaft and the unison-stop.

M is the unison-magnet, placed in the printing-circuit 2 2, (1 1 being the escapementciruntil a and b are freed by the attraction of N i by M. M may be operated in either one of several ways. A constant weak current may be maintained in 2 2, causing M to normally hold N, unison being effected by a complete break in the circut; or 2 2 may be normally uncharged, permitting the unison to go into op eration whenever the fixed number of revolutions have been made.

Many parts of a printing-telegraph are not shown or described, as they are of usual and well-known description, only such parts being shown and described as are necessary to show my invention.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, 1s

In a printing-telegraph, the combination of a type-wheel or type-wheels, an independent unison-magnet, a unison-stop, and a train of gearing, the unison mechanism being removed from the type-wheel mechanism, but acting thereon through the train of gearing, substan tially as set forth.

STEPHEN D. FIELD.

Vitnesses: Gno. W. CASPER, LUTHER E. SHINN.

s. At its other 

